Implement --restore-properties and --target-properties

[Peter2121]

Following issue #972
The implemented features permit to define the properties for destination dataset without loosing the initial properties that can be restored later.
For example, it is now possible to safely backup and restore datasets with different 'mountpoint' and 'canmount' options. It could be useful to backup the whole 'zroot' dataset to another host and then restore it, without manually changing any option on backup and on restore.

[ifazk]

Adding two additional flags seem a bit heavy. I think it would be easier to just add an option to add additional properties to the property blacklist.

Uses for --target-properties is already handled by recvoptions. By the time users needs to use --target-properties, they are already pretty advanced users, so I'd expect them to be familiar with recvoptions.

[Peter2121]

The most interesting part of my approach is backing up the properties to change and restoring them later. I don't see any way to implement this without the proposed flags.

[ifazk]

Sorry. I totally misunderstood what --restore-properties was doing, that's not a bad idea.